1. Field of the Invention
The present invention generally relates to a digital video signal recording and/or reproducing method, and a digital video signal recording and/or reproducing apparatus for recording and/or reproducing a digital video signal. More specifically, the present invention is directed to a method and an apparatus capable of recording and/or reproducing a digital compression video signal.
2. Description of the Related Art
The digital signal recording/reproducing apparatus for recording the digital compression video signal on the magnetic tape with employment of the rotary head is described in JP-A-8-273305. In this digital signal recording/reproducing apparatus, the digital compression video signal made in the packet format is subdivided based on a preselected byte number, and each of these packets is constructed of n bytes. Then, the sync (synchronization) signal, the identification information, and the error detection/correction code are added to the divided digital compression video signals to thereby constitute the block form. The digital signal recording region is formed by a preselected number of blocks to be recorded on the magnetic recording medium. Also, JP-A-8-273305 describes that the signal used to reproduce in the trick play mode is recorded as the digital compression video signal in this digital signal recording/reproducing apparatus.
However, in the case of the digital compression video signal by using a correlation between the frames, there are the following problems. That is, the video signal can be hardly decoded by simply deriving a portion of the data. Furthermore, the signal used to reproduce in the trick play mode can be hardly produced by simply deriving a portion of the data.
Also, since the head trace is not made coincident with the recording track during the trick-play reproducing operation, there is another problem. That is, it is practically difficult to discriminate the signal used to reproduce in the trick play mode from other digital video signals.
An object of the present invention is to provide a digital signal recording method and a digital signal recording apparatus, capable of readily producing a signal used to reproduce in a trick play mode from a digital compression video signal.
Another object of the present invention is to provide a digital signal recording method and a digital signal reproducing apparatus, capable of easily discriminating a signal used to reproduce in a trick play mode from other digital video signals.
A further object is to provide a digital signal reproducing method, a digital signal reproducing apparatus, and a digital signal decoding apparatus, capable of switching the normal reproducing operation and the trick-play reproducing operation.
The above-described object of the present invention may be achieved by such a digital video signal recording method for recording a first compression frame signal compressed without using a correlation between frames, and a digital compression video signal having preselected bytes of a packet format constituted by a second compression frame signal compressed with using the correlation between the frames, in which a third signal made of a packet containing the first compression frame signal is produced, and then is recorded in combination with the packet of the digital compression signal.
Another object of the present invention may be achieved by such a digital video signal recording method for recording on a magnetic recording medium by using a rotary head, a first compression frame signal constructed of a picture compressed without using a correlation between frames; a digital compression video signal having a preselected bytes of a packet format constituted by a second compression frame signal made of a picture compressed with using the correlation between the frames; and a third signal made of a packet containing said first compression frame signal; in which information indicative of an arrangement condition of signals is added to the third signal, and the resultant third signal is recorded on a predetermined region of a track on the recording medium.
The further object of the present invention may be achieved by such a digital video signal reproducing method for reproducing a first digital video signal constituted by a picture signal which has been recorded on a recording medium and compressed without using a correlation between frames and by another picture signal compressed by using the correlation between the frames; and a second signal produced from a picture signal compressed without using the correlation between the frames contained in the first digital video signal, in which:
the digital video signal reproducing method contains a first mode for reproducing the first digital video signal and a second mode for reproducing the second signal; in the first mode, the reproduced first digital video signal is outputted at the same timing during the recording operation; and in the second mode, the reproduced second signal is outputted at predetermined timing different from that of the recording operation.